To: atm{at}shore.net
From: Jim Burrows 
Reply-To: Jim Burrows 


At 09:42 2003-06-02 +0100, Richard F.L.R. Snashall wrote:

>Has anyone here considered the possibility of using something a stronger
>than Strehl ratio?  I'm thinking about something like the expected
>value of the error from the centroid, given intensity squared as the
>weighting function; or something like that.

The Strehl ratio is awfully hard to beat - it's got physics (wave optics),
history (Lord Rayleigh on), and the academic optics community consensus
behind it.  In fact, your "something" sounds like an intuitive
definition of the Strehl ratio .  I don't want to discourage the
search, however - maybe an ATM can come up with something better. 
Single-number mirror evaluations are nice and crisp, but one might start
with Suiter's preference, the EER, p. 197 (he decides to go single-number,
too, EER(1)).

         -- Jim Burrows
         -- mailto://burrjaw{at}earthlink.net
         -- http://home.earthlink.net/~burrjaw
         -- Seattle N47.4723 W122.3662 (WGS84)

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